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What are optional arguments in JavaScript Functions?
To declare optional function parameters in JavaScript, use the “default” arguments.
Example
You can try to run the following code to declare optional parameters −
<html>
<body>
<script>
// default is set to 1
function inc(val1, inc = 1) {
return val1 + inc;
}
document.write(inc(10,10));
document.write("<br>");
document.write(inc(10));
</script>
</body>
</html>
- Related Articles
- How to use named arguments in JavaScript functions?
- What are functions in JavaScript?
- How to pass arguments to anonymous functions in JavaScript?
- How to use Spread Syntax with arguments in JavaScript functions?
- What are callback functions in JavaScript?
- What are generator functions in JavaScript?
- What are immediate functions in JavaScript?
- What are Partial functions in JavaScript?
- What are JavaScript Math Functions?
- What are JavaScript Nested Functions?
- What are JavaScript Factory Functions?
- What are Rest parameters in JavaScript functions?
- Optional chaining operator in JavaScript.
- What are Self-Invoking Anonymous Functions in JavaScript?
- What is arguments object in JavaScript?
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